I want to mag a new internal mag box for my 404 Jeffery. It's built on 1917 Enfield and the gunsmith used a modified factory magazine.

I want to make a magazine that is dimensionally correct for the 404 Jeffery.

I have a 3D printed mold of the interior dimensions of the mag box. So as I bend the metal, I can check my fit.

Unfortunately, the piece is made from a soft material so I can't forcibly bend metal around it.

I looked at some inexpensive hand metal brakes, but they make 90 degree bends, I need a radius on mine.

I watched some internet videos of DIY metal brakes with tube steel of different diameters for the radius bend.

Any simple hobbyist metal brakes out there with radius options? Other ideas?

Does anyone out there make custom magazine boxes?

I also thought about using the 3D part as a negative mold on the stock with some epoxy and make a molded in magazine.

I just use bar stock I machine to the right dimensions to form around; not sure where a radius is needed. Factory boxes do not have radii.
I have no means for 3d printing so can't comment on that.

My buddy has a metal roofing company - forms lots of his own stuff. Maybe try that?

Clamp one end of it to a 2x10 and hammer it around a length of drill rod.

Yeah, what dpcd said, why do you want a radius?!

If you have a 3d printed master, investment cast it in aluminum or make a bondo/body filler casting of it and use that for a master. It's not difficult to copy something once you have a actual master made.

quote:

Originally posted by Macs B:
If you have a 3d printed master, investment cast it in aluminum or make a bondo/body filler casting of it and use that for a master. It's not difficult to copy something once you have a actual master made.

That's an interesting idea

Block of aluminum. cut out a male to use as a bending jig. file the edges round.

Even my $135 travers bandsaw can cut that out.

one thing I noticed that the steel boxes are almost like spring steel.

OR

use the male as a form for a carbon fiber or Kydex box.

Print a solid punch that has exterior dimensions that are the same as the interior dimensions of your proposed magazine box.

If your printer has the capability to utilize some of the higher strength media or even semi-metallic media those should serve you well and should be able to take some moderate abuse from forming sheet metal around them.

While not magazine design there's plenty of insight of the system in D'Arcy Echols blog posts about fitting the magazine box to the receiver.

Echols blog post 1

Echols blog post 2

Echols blog post 3

Photos of Mag box punch and die

That's a good article by D'Arcy.

I did a make shift "embedded" magazine yesterday to the dimensions of my 3D printed part - used sheets of styrene temporarily attached to inside of stock to create the right dimensions. Opened up the bottom of the receiver to match the wider dimensions. And then stood in the front yard cycling through 5 dummy rounds with 4 different bullets (varying location in magazine) for a while to make sure it was 100%.

Now, gotta decide whether I 1) make a drop-in mag (I like the Kydex and CF idea) 2) Replace the styrene with metal and permanently bond to rifle 3) use the 3D part as a negative mold and mold in the magazine with epoxy (the rifle is already fully epoxy bedded).

All I know is that I'm happy I have 5 rounds down in my 404 now

Here is the last Enfield box I made, yes its for a 404 Jeffery.
4 pieces of steel with the corners welded.
Do not spend too much time over thinking it.

I finally got the magazine box done. I was making a prototype and then was going to make some pieces for my friend to weld for me, but went ahead and used the prototype - just some bent 22 gauge steel. I used a 3D printed negative of the magazine box dimensions as a guide. It is based on an original 404J factory dimension.

Anyway, fits 5 down now and feeds flawlessly. Not as elegant as a factory Heym mag or any of the custom one piece bottom metals, but it works!

Insert

3D printed negative

Bottom View

The feed lips are intact on the bottom of the receiver?

What kind of 22 ga. steel, do you (need to) harden it?

quote:

Originally posted by richj:
The feed lips are intact on the bottom of the receiver?

What kind of 22 ga. steel, do you (need to) harden it?

Feed lips are there, but recontoured and opened up about 0.025" Actually, there was room to open the action more in the rear and leave the front alone, but I didn't do the work.

The insert is zinc galvanized 22 gauge steel. Going to check the recoil on it at the range. Don't think I need to harden it. Cut it by hand and filed it. If it's a problem, I'll add a shim plate to the front. There is about a .030" gap between the mag insert and stock.

BTW - I was very close to just using the 3D printed block as a negative mold and making a built in epoxy box. Just did want to dork with the epoxy everywhere and worried about perfect alignment.